Data from a send queue is sent only if there is enough space in a window, so when we restore unacked data, we need to expand a window to fit this data.
Currently we don't do this and tcp_acceptable_seq() returns tcp_wnd_end(tp) instead of tp->snd_nxt. The other side drops packets with this seq, becuse tcp_sequence() returns false (seq < tp->rcv_nxt). Cc: Pavel Emelyanov <xe...@parallels.com> Cc: "David S. Miller" <da...@davemloft.net> Cc: Alexey Kuznetsov <kuz...@ms2.inr.ac.ru> Cc: James Morris <jmor...@namei.org> Cc: Hideaki YOSHIFUJI <yoshf...@linux-ipv6.org> Cc: Patrick McHardy <ka...@trash.net> Signed-off-by: Andrey Vagin <ava...@openvz.org> --- net/ipv4/tcp_output.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 79a03b8..b36f968 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -75,6 +75,10 @@ static void tcp_event_new_data_sent(struct sock *sk, const struct sk_buff *skb) tcp_advance_send_head(sk, skb); tp->snd_nxt = TCP_SKB_CB(skb)->end_seq; + /* All sent data have to fit into the window */ + if (unlikely(tp->repair) && before(tcp_wnd_end(tp), tp->snd_nxt)) + tp->snd_wnd = tp->snd_nxt - tp->snd_una; + tp->packets_out += tcp_skb_pcount(skb); if (!prior_packets || icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { -- 2.5.5